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A093846
Triangle read by rows: T(n, k) = 10^(n-1) - 1 + k*floor(9*10^(n-1)/n), for 1 <= k <= n.
6
9, 54, 99, 399, 699, 999, 3249, 5499, 7749, 9999, 27999, 45999, 63999, 81999, 99999, 249999, 399999, 549999, 699999, 849999, 999999, 2285713, 3571427, 4857141, 6142855, 7428569, 8714283, 9999997, 21249999, 32499999, 43749999, 54999999, 66249999, 77499999, 88749999, 99999999
OFFSET
1,1
COMMENTS
10^(n-1)-1 and the n-th row are n+1 numbers in arithmetic progression and the common difference is the largest such that a(n, n) has n digits. This common difference equals A061772(n).
EXAMPLE
Triangle begins:
9;
54, 99;
399, 699, 999;
3249, 5499, 7749, 9999;
...
MAPLE
A093846 := proc(n, k) RETURN (10^(n-1)-1+k*floor(9*(10^(n-1)/n))); end; for n from 1 to 10 do for k from 1 to n do printf("%d, ", A093846(n, k)); od; od; # R. J. Mathar, Jun 23 2006
MATHEMATICA
Table[# -1 +k Floor[9 #/n] &[10^(n-1)], {n, 8}, {k, n}]//Flatten (* Michael De Vlieger, Jul 18 2016 *)
PROG
(PARI) {T(n, k) = 10^(n-1) -1 +k*floor(9*10^(n-1)/n)}; \\ G. C. Greubel, Mar 22 2019
(Magma) [[10^(n-1) -1 +k*Floor(9*10^(n-1)/n): k in [1..n]]: n in [1..8]]; // G. C. Greubel, Mar 22 2019
(Sage) [[10^(n-1) -1 +k*floor(9*10^(n-1)/n) for k in (1..n)] for n in (1..8)] # G. C. Greubel, Mar 22 2019
CROSSREFS
KEYWORD
base,easy,less,nonn,tabl
AUTHOR
Amarnath Murthy, Apr 18 2004
EXTENSIONS
Corrected and extended by R. J. Mathar, Jun 23 2006
Edited by David Wasserman, Mar 26 2007
STATUS
approved